This invention relates to a fan, more particularly to one which has radially interconnected oblique planes so as to establish a semi-spherical fluid flow field.
Because a conventional fan blade consists of a single oblique plane which is normally twisted to form part of a helical surface, conventional fans can only create an air flow in the direction of the motor shaft axis. This axial air flow field is too small to meet the need of the user. For example, a ceiling fan can only blow air toward the area just below it. Also, an electrical exhaust fan can only suck air from the area just below it. It is preferable to increase the air flow range, however, from the standpoints of utility and economics.